Hi, psychologist here,
I would like to put my 2 cents bc I see a lot of people talking about OCD and phobias, pardon me some mispelling because Im not native
An OCD is, by definition, something you can't control, that`s the part about being a compulsion, sure, let say people can go and do things and try to fight this impulsive sensation to do the compulsive action, but in the end they can not stop thinking about it, that's because is an obsession too. People who have this kind of disorder tend to be overly neurotic about contexts and actions so they can control the situation they are in, that way they can do the obsesive-compulsive action they need to do before of after an action, e.g: Anna really need to switch the lights on and off 20 times before enter a room, if Anna don't do it, then she is not enter the room, if you try to force her to enter then she is gonna decompensate, maybe she will faint, scream, froze, there are a lot of reactions, but usually their reactions are what I mentioned.
In the other hand, a phobia is an irrational fear, the object of fear can be a object, animal, person or a situation, although in can be hate too. People who have XXXXXphobia try their most to not being exposed to a situation where their object of fear/hate is present, and they will do herculean efforts to ensure this.
The reason all of the people here talk about the two is because people with phobias tend to do obsesive-compulsive actions, so they can ensure a context where the object of displeasure is absent.
In this case, obviously fictional, Isagi-san have a big, enormous feeling of displeasure when she is in physical contact with filth, being the case of objects or people, something that the author seems to simplify as "I don't like to be touched". She is not a germophobe, in anywhere in this chapters is stated that she fear or hate germs, her obssesion is about not being in contact with filth, the confusion comes because cleanliness is the reaction we can expect of this two phenomena.
We can see examples in chapter 196.1 when she clean the teacher desk, clean her desk after find a hair, toss her blouse off the window when the classmate touch her, etc., and this give off the feeling that is better not to get in contact (not pun intended) with her, because this kind of people are really difficult to interact with, and nobody wants to be treated like a shit.
Plus this characteristic, in this chapter we can see that Isagi-san is a very considerate person, and generally speaking, a very harsh and direct person, the kind of person that are are often see as prideful and full of themselves when you meet them.
Well, that said, I like her design and character, and the fact that she don't treat Komi like a god, but I can understand that people are put off because Isagi is very neurotic in his demeanors, and although is very direct with her words, she don't put in words her intentions and good will.
peace 😁